Slashdot Mirror

Lotsa links here...

First of all, the 2002 Burning Man project I did that involved a couple hundred RGB LEDs spinning in a persistence-of-vision-based nighttime animated display. Here is the best picture of it. This is the page about the development details.

The LEDs I used were manufactured by Kingbright. The model I used, the LF819EMBGMBC, is big (10mm) and relatively bright for an RGB LED. I couldn't find any U.S. retailers that actually told the truth about whether they stocked them, so I ended up buying 400 directly from Kingbright for I think a little more than $2.50 each. I still have a few left.

Atmel AVR microcontrollers are just a few bucks each, easily programmable with the STK-500 programmer, also cheap at around $80. I used the ATMega8, which was more than sufficient for my needs. I imagine the original Slashdotter could use one of the ATTiny MCUs, since it really needs only 3 or 4 I/O lines (fewer depending on how many helper circuits you decide to use).

The boards were manufactured by PCBExpress and I was very happy with them. The CAD/CAM software was Eagle, which except for some crashing/redrawing bugs was really amazing. The version I used was free. I tried to buy it but CadSoft has (had?) a fairly crazy pricing scheme that actually left you worse off in terms of acceptable usage if you paid them money than if you used the free version.

The best part of using the Atmel MCU was that GCC can cross-compile for it. So you're basically writing regular old C code but it runs on a little tiny piece of silicon. You'll want to subscribe to the quite active avr-gcc mailing list. Save every message from Marek Michalkiewicz; in my opinion he's the god of GCC-for-AVR development.

because I installed Kivio [thekompany.com] on my laptop so I could build circuit diagrams on my laptop.

Why not use a proper schematic entry program? Hell it's even free and will do autorouting for 2 planes and a restricted (but generous) board size for that price.

are we currently able to put together a free version of the big convergence media center others are trying to do?

Yes. I have one. My file-server contains a DVB card (receives digital satellite, hard-decodes MPEG and exports audio and video) and an IR receiver, which are both cabled up to my living room.

As other posters report, there are similar commercial solutions on- or close-to- market, but this is all open, all free.

And yes, it's all integrated. The centrepiece is VDR (FAQs, plugins here) (please don't hurt the webservers). Plugins enable MP3, DVD, SVCD, DiVX and more.

The drawbacks, you ask? It's Linux. (ducks for cover) What I mean is that, like so many other Linux projects, the developers are much more interested in building new features than working on stability. The code is also growing in a fairly uncontrolled way, although the developers are working on that problem.

In my opinion, this system will never be as polished as the commercial solutions. But it will remain a hell of a lot more flexible (you want Ogg? You got it!). And it's a lot of fun. :)

>My TV has a better picture.

Say what now?

>Season Passes.

If only it were Europe and we had standard DVB stuff, instead of the duopoly in non-standard Satellite TV we currently have. It would make viewing TV on your computer a pleasure, and you could buy any channel you want, not some moronic package that makes you buy a wildlife channel because you want TLC.

>Searching by category. Everyone so often, I like to go look at say, all the movies, coming up & Tivo the ones I've wanted to see.

Again, this is really more the result of the duopolistic control of satellite TV (soon to be monopolostic in America, unfortunately) rather than something that's actually impossible. You can also put some of the blame on Canada for our inane CRTC.

>The interface. Any way you cut it, Tivo did a great job here.

This is true. Although there are Tivo-alike projects out there (running on Linux!), however, the ones with Tivo-style features are for DVB. Some of them approach many Tivo features, I'm told.

Here's one of the projects. Here's some that'll work minus the DVB (I think).

If you want to go ahead and give DVB a try, there's some free programming on Telstar 5, but I doubt it'll be anything like what you get on DirecTV.

Dunno which part of the world you live in, but if you're in an area where DVB is used, check out VDR, it's da bomb.

It is a bit pricey to get DVB-T/S/C cards right now, especially the DVB-C digital cable cards, but if you are able to get digital TV, the VDR software has all the necessary features, and because there is no re-encoding of video stream, the reception quality is preserved. Program guide is streamed along with the programs. Almost only available in Europe though.

The writer has VDR in his links too, but this is it again: VDR. Slashdot article about it can be found in here. I think the software has evolved and the availability of DVB cards has improved a bit since then so that if you passed this option last time it might be worth it to check it out again.

This guy has already been working on something similar and already has quite a nice gui. He even got an article in Popular Science a few months back. Seems to have done a much better job too IMO.

The VDR program can record shows from a digital source. It uses the Linux DVB drivers. At work, we succesfully used it with a Hauppauge DVB-S card connected to an Astra feed. However, this is in Europe, I'm not sure something compatible exists in the US (OpenCable?).

Try this one:
Linux based VDR
You need a DVB-stream(sat, cable, antenna) from somewhere...

This site has the terrific and very active VDR project. It has full DVB support, full PVR support, and plugins for DVD playback, DivX, MPEG-4, MP3, LCD displays and more... If you want GPL Digital TV this is the place to go. Sign up to the mailing lists and contribute to this fantastic example of open source working well.

VDR records in MPEG2 and plays DVD / DIVX / MP3 / SVCD / ... I love it :)

I finally broke down and built a TV machine last summer.. I mainly used it to play Divx movies--both ones I ripped from my DVDs myself and ones I downloaded from Morpheus.

Remote Control:

1. I bought an IRman and got it working with Winamp's VidAmp..
2. At first, I kept no mouse or keyboard on the box. I opted instead to use the remote,
   TweakUI-configured auto-login, and VNC (from my laptop already wired-up in the living room.

1. I tore down a mid-tower case and buffered all of the metal joints with duct tape as I built it back up.
   This eliminated any inherent case rattle.
2. I layed the side and reconfigured my entertainment center's shelves to accommodate it.
3. The case had a interesting configuration of fans (combinations of Thermaltake "smart" fans and things)
   to try to keep the AthlonXP 1700+ and three Maxtor drives (one 30GB and two 80GB) cool.

What have I learned?

1. I *have* to have TiVo functionality and soon.
2. Morpheus/Kazaa and other online sources of movies are dying.
3. Drives fail quickly if not properly cooled.
4. Drives tend to fail anyway or have the remote possibility of very quickly losing 100 of your
   hard-earned movies in the event of failure.
5. Almost no matter what, a TV PC is going to be too loud to enjoy having in the living room.

What will I do differently next time?

1. I will build two different boxes--one bare and quiet set-top box or something in the living room and the other a
   nasty, tricked-out, noisy system to handle all of the grunt-work in another room.
2. IDE RAID. 'nuff said.
3. Linux--as much as possible. I will actually make the full effort to get away from Windows and build
   On-Screen Display menus and things.. One of the bottom lines of my experience is that Windows/FAT32
   *kills* drives.
4. I *have* to have TiVo/PVR/DVB/DVR/VDR functionality.. I could theoretically
   have one DVB card in the
   STB to add pause-live-TV functionality. For the setup and recording of other scheduled TV programs and movies, the "big box" in the other room that will have somewhere in the
   neighborhood of 4 or 5 DVB cards. This is fine for Digital Cable.. If I had a dish, it would
   likely be very different.
5. Rip, rip, rip. Get those DVDs archived onto file and quit letting other peoples' copies be sufficient.
   I really didn't do all *that* bad.. I had ripped somewhere around 60 of the DVDs myself.
   I've really got to say this--AVI-archived DVDs beats the friggin bug juice out of any multi-DVD player.

Here are some more related links..
LinuxDVB
VDR

You can find a linux based PVR here. The only disadvantage is that one needs a DVB-Sat card.
Or two if you want to do timeshifting.

Oh please. I build stuff all the time at home and in the lab, last time I checked, places like Maxim have -free- sample quantities in packages you can work with if you have a good iron (SOIC, et al). Getting boards done in small volume is cheap, use a tool like Eagle, which is even available for Linux (but not OS X, doh!). Spend a few bucks and get a quality board done at a internet based low volume PCB shop.

There are evil packages, but the truth is a lot of the prototyping and test work is done on hand placed boards. Even evil packages can be used if you get an adapter board, there are a few of them out there.

What's more telling is that now instead of messing with token things, and "wow, I actually got something to show up on the display", you can do some real work with your computer and designs and instruments. I realized awhile ago I was spending far too much of my time tinkering with things and not enough accomplishing things.. but I guess some of that is the Linux mentality too. :) Now I figure out what I want to accomplish and use the best tool, rather than attempting to make everything into a nail for my hammer.

For $300 or so you can even get prototype boards for FPGAs if you want to do custom hardware. $150 will get you a decent micro development system, and AVRGCC is gnu, runs on linux and windows (but not OS X :), and lets you program cheap cheap cheap AVRs to do just about anything you want. Mix with ADCs and some transistor fed relays or PWM control to do whatever. You can get software to turn your PC into a function generator to test, or if you hunt around, you can get a nice old digital oscilloscope AND a real function generator AND a bus analyser suitable for 8 bit micros (or more) for less than the cost of a PC 4 years ago.

Same thing applies for most other scientific equipment. Be careful when sourcing chemistry gear, even broken stuff, or you might have the DEA paying you a little visit if you happen to live in the USA. If high voltage fun is your bag, there's companies for that. There are even companies that sell cold fusion experiment kits - although most of the magic there seems to be in the process used to create the electrodes.

I contend there's never been a better time to BE a amateur scientist! You can actually afford to have a decent lab since last year's gear can be tracked down on the cheap.. and accomplish real work, too! How many high res night shots could you store on a $200 80gb drive? Etc, etc, etc, etc.

Death of amateur science predicted! Film at 11.

It like the remote control board the best. I assume it can be easily programed to flash 12:00am all the time.

SD

/. has gotten more popular! That's probably why we're seeing more DOS attacks! I mean, there's been one (Linux PVRs) today already.

Or, maybe not...

Couldn't one create a distributed PC client that would compile the TV listings from around the world (Maybe leeching content off of TVGuide.com).

Even more interesting than that idea is that you don't need to chew on HTML to get the listings. See XMLTV.

Now that I have some free time on my hands, I think I'm going to start that home PVR project based on XMLTV. You don't need to sacrifice useability either, as there is code out there for on-screen menuing. Nice.

Linux people do buy software. Myself, I recently bought Eagle and Qt (commercial license).

The problem is with products themselves. It is virtually out of question to buy WP into an office that is built around MS Word or StarOffice formats. CorelDraw may be good, I used it very long time ago, but Corel is dwarfed by rows and rows of Adobe products; basically Adobe Illustrator is the #1 in vector graphics, while Adobe Photoshop became a de-facto standard (and a platform) for raster images. Corel lost the market on its own, and Linux sales, targeting new customers, only reflect that.

DVB is more common in Europe I guess.

I have the "biggest" Hauppauge DVB card, the WinTV-DVBs in my box. This is the card for sattelite broadcasts. A WinTV-DVBc exists as well which is for cable.

I use it daily. Linux support is nice !There are several projects around this family of cards (since they are all built on the same reference design, you can even exchange their software and driver on Windows I have been told). The card I am talking has hardware decoding of the media-stream. There exists a smaller one from Hauppauge which does the decoding with the CPU.

• The main site. Hosts the driver, has implemented the MHP (together with NOKIA, opensourced), and has references to the VDR project (see third link)
• the DVB driver for Linux (download page)
• Linux Video Recorder (DVB) (German, very detailed instrctions on setup and build.
• The VDR main-site
• Since the VDR was built to use the TV-Out the picture will go there. However, since they use the V4L interfaces one can use xawtv, KTV (or so) as well as the specialized Kvdr (which brings the complete VDR to the desktop). It is here (as well as an IPoverIEEE1394 and DV backup project)
• Extensions for the VDR
• VDR-NFSroot (also interesting)
• Resource and FAQ site
• Site of general DVB-s interest
• Now this guy has a dish in his garden that has several meters in diameter :-) (WARNING: for freaks)
• On EfNet IRC there is a channel #LinuxDVB. It is in German but since all Germans (well most) talk english they will help out for sure.

All in all I can say, that this is well supported and heavily used, at least in Germany. MPlayer is going to get DVB support soon (they will use its MPEG decoder for MPEG decoding).

I do not use the card for data-services, however, there is a driver for this on the drivers main-site. DVB data is one-way, so one still needs to have a modem connection open for upstream. I have been told that due to the whole continent using two or three providers the resources (bandwidth) on the sattelite is very used and xfer rates drop easily down to ISDN speed). So I would not recommend this (unless your family has rented their own transpoder).

There are people who have two or three of these cards in a small footprint Linux box, that they access over http or ssh and which is hooked to the TV. Along with some big drives they use it solely as VCR with timeshifting and also for DVD and MP3 playback (which is possible). The VDR project is LIRC compatible and has support for the WinTV-DVBs rev 2.1 IR control as well

1. PVR - record TV to hard drive, pause live TV etc.
2. basic local programming guide
3. advanced local programming guide (recommendations, sophisticated search etc.)
4. modular component fits well into home AV system

1. monthly fee
2. some tracking of user activity

1. find a way to get TV listings for your locality
2. find some PVR software (if it didn't already come with your video hardware)

Just compare http://www.linux4.tv and http://embedded.censoft.com/. Seems like the guys at Century Software are trying to get someone to program software for free so they can sell their set-top boxes later.

BTW, simliar projects have been around over here in Europe for quite a while - and those require no registration to download software and specs. Just have a look at http://dbox2.elxsi.de/ or http://www.cadsoft.de/people/kls/vdr/ ;-)

Well, I am thinking more in terms of usability when going digital. Think about this, I can record as many shows as I want without worrying about tapes. I can assign names to timer slots, and when I get home, I will be presented with a list of shows I have recorded. I will just have to select a particular show, and presto, I will be watching it. With tapes, I have to figure out which tape to pop in. Sometimes, if I record two shows back-to-back and I have only watched one, I can't reuse that space because I still have another show on tape... blah... blah... you know what I mean... the various advantages of going digital.

I don't get it... isn't this easy (at least for people in the business)? Just pop in a HDD and an MPEG2 chip, and you have a digital VCR? Well, I agree there are advantages with downloading the TV schedule, but can't we have a low-end model that is just the digital version of an analog VCR?

Well, if someone can point me to a good and affordable MPEG2 encoder card (with Linux drivers), I'd be glad ot build one myself. I have done some searching on Google, so far the furthest ahead is the Video Disk Recorder project. Man, the DVB-S card itself is the price of a TiVO!
---

Besides, with digital TV/HDTV you really do want to get the original MPEG2 stream instead of decoding it once, and then encoded again when you record. Any set-top boxers/satellite recievers with firewire out?

I don't know about the availability of DVB (== Digital Video Broadcast, a standard developed and deployed in Europe for digital TV in MPEG-2 format) content in the U.S., but there are solutions available that do just that. Have a look at http://www.linuxtv.org or http://www.cadsoft.de/people/kls/vdr/

This question has been asked no fewer than two times before, and one time, I even answered in +3 detail on exactly what would be needed to make a PC-based TiVo.

But that's okay, let's rehash.

Since we're going entirely software-based, e.g. you're sitting a normal, icky PC in your stereo rack, or you're just using your PC as normal, you probably don't have a hardware MPEG encoder. The best you've probably got is a Matrox card with onboard MJPEG compression, and I don't think the Linux drivers support that.

Now, assuming you already know how capture a video stream and pipe it to an MPEG encoder (and trust that your system is fast enough to not drop too many frames; think P3/500 or better), the only thing you really need to do is add in TV listings, and integrate them into channel changing and record functionality.

Copy and pasted from my previous post, channel guides are easy. Just have a Perl script rip and reformat any of the listings from the online providers, including Excite TV, Ultimate TV, GIST TV (which also provides the Yahoo TV listings), Ask TV (in the UK), Click TV (what TiVo uses), TV Quest, TV Grid or TV Guide Online.

As for integration, a lot of this work has already been done, at least for satellite TV streams. Klaus Schmidinger produced his Video Disk Recorder which performs channel guides and VCR functionality on his Linux PC, for his satellite TV using a PCI card. All GPL'd, so feel free to port it over to plain old TV cards, too.

--Vito

This Nokia thingy is just a normal PC. You can record MPEG-2 streams from European satellites to your harddisk with a DVB-S pci card like the one from Siemens, which is the same card as the Hauppage WinTV DVB and a couple of other manufacturers. There are GPL'ed linux drivers for this card and someone even hacked up some digital vcr linux software for it, see here.

This was a thread during the whole TiVo hacking topic. Jim Buzzbee was cool enough to post with a link to a wonderful individual who hacked together his own TiVo/Satalite reciever with full menus and even a remote. The plans are here. I really wanna make one if I can scrounge up the money!!

They even have a freeware version which is ok for weekend projects.

http://www.cadsoftusa.com/ or http://www.cadsoft.de/

This software is not a toy, it is one of the best pcb design packages available on any platform, and it is reasonably priced. Life is good to us electronics engineers !

Don't be too hard on TiVo. Realize that they are likely selling the hardware at a loss depending on customer's monthly subscription to make up the difference.

They are also walking a fine-line with the MPAA regarding recording copyrighted material. The MPAA is afraid that people will make a digital recording of first-run (Pay per view/HBO, etc ) material and start distributing it on the net. If the MPAA gets unhappy, they'll attempt to shut TiVo down. TiVo must at least attempt to keep the recorded material "protected" or they'll be put ot of business by the MPAA.

If you are interested in doing a box yourself, Here's a page describing the creation of one. This guys advantage is that he is dealing with a satellite receiver so the data is already professionally compressed.

One of the leading German EDA companies, CadSoft has already released a Linux version of their PCB CAD package which is actively marketed the same way as the DOS and Windows 95/NT versions. So, apparently, there is a market.

-- Jochen

These people ported their DOS/Windoze Stuff
to Linux:
http://www.cadsoft.de. They were
stuck with DOS/Win for a decade but decided
recently to support Linux AFAIK.

Their Product is called EAGLE and they
have a "free" Version for half-euro boards.
It's pretty cool.

They are located in Germany (as I am), but
their hp is english.

greetings,
Jurij